It is an interesting exercise to calculate the probabilities of suspicious deaths of 20 Dealey Plaza witnesses. The 20 are among 122 JFK-related suspicious deaths in the JFK Calc spreadsheet database in the 15 year period from 1964-78.

Furthermore, 14 of the 20 witnesses testified at the Warren Commission, 4 were sought to testify in the Garrison trial, 2 at the Church Senate hearings and 3 at the House Select Committee on Assassinations (HSCA).

The probabilities of JFK witness deaths for various groups have been previously posted: Warren Commission, London Times actuary,Garrison/ Shaw, Church, HSCA, Simkin Educational Forum, JFK-related 1400+ witness reference “Who’s Who in the JFK Assassination”.

The probability of 8 ruled unnatural deaths assuming 300 witnesses is 1 in 1500. But a statistical analysis of the expected number of accidents, suicides and natural deaths indicates that approximately 13 were homicides, so there were 15 total homicides out of 20 suspicious deaths.

Assuming 2X the national homicide rate, let’s calculate the probabilities of 8 and 15 homicides.

For 300 witnesses, the probability of 15 homicides is 1 in 175 trillion.
The probability of 8 homicides is 1 in 700 thousand.

For 500 witnesses, the probability of 15 homicides is 1 in 130 billion.
The probability of 8 homicides is 1 in 18 thousand.

The HSCA in 1979 claimed that the London Sunday Times actuary’s probability calculation of 18 material witness deaths in the three years following the assassination was invalid. The reason: the witness universe was unknown. But the HSCA did not consider Dealey Plaza witnesses or other defined witness groups. The HSCA would have confirmed the actuary if it did a true analysis.

The actuary’s 1 in 100,000 trillion probability is matched given 15 homicides of 385 Dealey Plaza witnesses over 15 years, assuming the average national homicide rate (0.000084).